Barteria fistulosa and B. dewevrei, central African rain-forest trees, provide nesting cavities for Tetraponera aethiops and T. latifrons ants, respectively, which protect them against herbivores. To compare protection efficiency between these two symbioses, for 20 plants of each species in two sites in Gabon we measured the time elapsed before ants reached a focal leaf, for host leaves that were undisturbed, damaged (cut with scissors) or subjected to slight vibration (mimicking such damage), and for damaged leaves of the non-host Barteria species. Tetraponera aethiops displayed stronger protective behaviour than did T. latifrons. Time to reach a damaged host leaf (4.5 ± 2.6 min, mean ± SD) did not differ significantly from time to reach a leaf subjected to slight vibration (5.2 ± 3.0 min) for T. aethiops, but response to a leaf subjected to slight vibration (9.5 ± 1.9 min) was significantly slower than that to a damaged leaf (7.8 ± 1.9 min) for T. latifrons. The faster response of T. aethiops to slight vibration may have masked a response of this species to chemical signalling. Both ants reached damaged host leaves faster than damaged leaves of the non-host Barteria sp., indicating host plant specificity in ant responses.

Vascular surgery patients are nutritionally vulnerable. Various malnutrition screening and assessment tools are available; however, none has been developed or validated in vascular patients. The present study aimed to: (1) investigate the validity of four commonly administered malnutrition screening tools (Malnutrition Screening Tool (MST), Malnutrition Universal Screening Tool (MUST), Nutrition Risk Screen-2002 (NRS-2002) and the Mini-Nutritional Assessment – Short Form (MNA-SF) and an assessment tool (the Patient-Generated Subjective Global Assessment (PG-SGA)) compared against a comprehensive dietitian’s assessment and (2) evaluate the ability of the instruments to predict outcomes. Vascular inpatients were screened using the four malnutrition screening tools and assessed using the PG-SGA. Each was assessed by a dietitian incorporating nutritional biochemistry, anthropometry and changes in dietary intake. Diagnostic accuracy, consistency and predictive ability were determined. A total of 322 (69·3 % male) patients participated, with 75 % having at least one parameter indicating nutritional deficits. No instrument achieved the a priori levels for sensitivity (14·9–52·5 %). Neither tool predicted EuroQoL 5-dimension 5-level score. All tools except the MNA-SF were associated with length of stay (LOS); however, the direction varied with increased risk of malnutrition on the MUST and NRS-2002 being associated with shorter LOS (P=0·029 and 0·045) and the reverse with the MST and PG-SGA (P=0·005 and <0·001). The NRS-2002 was associated with increased risk of complications (P=0·039). The MST, NRS-2002 and PG-SGA were predictive of discharge to an institution (P=0·004, 0·005 and 0·003). The tools studied were unable to identify the high prevalence of undernutrition; hence, vascular disease-specific screening and/or assessment tools are warranted.

The performance of a new point-of-care diagnostic (Mastatest), an on-farm test designed to identify bacteria and provide antibiotic sensitivity testing information from milk samples, was compared with standard microbiological culture methods. A total of 292 milk samples from clinical mastitis cases in dairy cows on New Zealand dairy farms were examined, and latent class analysis was used to estimate the performance characteristics of both tests. Two hundred and fifty-six samples (87.7%) demonstrated bacterial infection in standard culture, and 269 (92.1%) using the point-of-care diagnostic. The most common bacterial species detected was Streptococcus uberis, found in 195 samples (66.8%) using standard culture and 190 samples (65.1%) using the point-of-care diagnostic. Latent class analysis found no significant differences in test characteristics between the point-of-care diagnostic and standard culture. The estimated sensitivity and specificity of the point-of-care diagnostic against all targets combined were 94.6 and 72.1% respectively; the corresponding estimates for standard culture were 90.5 and 73.9%. Comparison of antibiotic susceptibility testing using the point-of-care diagnostic and the reference method showed similar trends and, in some cases, identical MIC50 and MIC90 values, with at most one antibiotic dilution difference.

The Bipolar Spectrum Diagnostic Scale (BSDS) is widely validated and used as a screening tool for bipolar disorder. However, there is no BSDS validated version for its use in Mexican population. The aim of the present study was to examine the BSDS diagnostic capacity, and to evaluate its criterion validity and internal consistency for its use in Mexican psychiatric patients. We recruited 200 patients who attended the psychiatric outpatient service of a Mental Health Specialized Hospital and were screened for bipolar disorder using BSDS. To determine the cut-off point, sensitivity and specificity, we used the SCID–I diagnosis as the gold standard in 100 participants with bipolar disorder and 100 with major depression. Internal consistency according to Cronbach’s coefficient alpha was .81. The area under ROC curve for the overall discriminability of BSDS against the criterion of SCID–I for bipolar disorder was .90. Finally, a cut-off value of 12 reached the most stable sensitivity and specificity, with predictive powers higher than .80. In conclusion, the properties of the scale including internal consistency, sensitivity and specificity, make of BSDS a valuable instrument for screening bipolar disorder in Mexican psychiatric population.

Understanding how individual parasite traits contribute to overall fitness, and how they are modulated by both external and host environment, is crucial for predicting disease outcome. Fungal (chytrid) parasites of phytoplankton are important yet poorly studied pathogens with the potential to modulate the abundance and composition of phytoplankton communities and to drive their evolution. Here, we studied life-history traits of a chytrid parasite infecting the planktonic, bloom-forming cyanobacterium Planktothrix spp. under host genotype and thermal variation. When expressing parasite fitness in terms of transmission success, disease outcome was largely modulated by temperature alone. Yet, a closer examination of individual parasite traits linked to different infection phases, such as (i) the establishment of the infection (i.e. intensity of infection) and (ii) the exploitation of host resources (i.e. size of reproductive structures and propagules), revealed differential host genotype and temperature × host genotype modulation, respectively. This illustrates how parasite fitness results from the interplay of individual parasite traits that are differentially controlled by host and external environment, and stresses the importance of combining multiple traits to gain insights into underlying infection mechanisms.

Factors that drive parasite specificity and differences in infection dynamics among alternative host species are important for ecology and evolution of host–parasite interactions, but still often poorly known in natural systems. Here, we investigated spatiotemporal dynamics of infection, host susceptibility and parasite-induced changes in host phenotype in a rarely explored host–parasite system, the Australapatemon sp. trematode infecting two sympatric species of freshwater leeches, Erpobdella octoculata and Helobdella stagnalis. We show significant variation in infection abundance between the host species in both space and time. Using experimental infections, we also show that most of this variation likely comes from interspecific differences in exposure rather than susceptibility. Moreover, we demonstrate that the hiding behaviour of E. octoculata, but not that of H. stagnalis, was impaired by the infection irrespective of the parasite abundance. This may increase susceptibility of E. octoculata to predation by the final avian host. We conclude that differences in patterns of infection and in behavioural alterations among alternative sympatric host species may arise in narrow spatial scales, which emphasises the importance of local infection and transmission dynamics for parasite life cycles.

Angiostrongylus vasorum is a cardiovascular nematode increasingly found in dogs and foxes in endemic foci throughout Europe. The present study evaluates ELISAs for detection of circulating antigens and specific antibodies against A. vasorum in foxes. Blood and worm burdens (WBs) from carcasses of 215 Swiss wild red foxes (Vulpes vulpes) and from 75 farmed foxes of different age groups experimentally inoculated once or repeatedly with infective doses of 50, 100 or 200 third-stage larvae were obtained. Antigen detection in the naturally infected Swiss foxes had 91·2% sensitivity and 89·4% specificity, whereas the corresponding figures for antibody detection were 42·2 and 92·0%. The experimentally infected foxes became positive for circulating antigens 5–10 weeks post-inoculation (wpi) and remained highly positive up to 22 wpi, irrespectively of further challenge inoculation. The antibody responses in the same foxes were highly variable: high optical density (OD) values were reached 5–7 wpi in all animals, followed by a decrease in over half of the animals despite accumulating and consequently high WBs resulting in persistent infections. After each challenge, a slight increase of OD values was observed 7 weeks later. We hypothesize that infected foxes develop a variable and non-protective immunity. Such parasite tolerance allows long-term survival of A. vasorum in the animals, and may explain why the parasite appears to spread rapidly within a fox population, an epidemiological dynamic that is evident in many parts of Europe where A. vasorum has been found over the last decades.

A latent tuberculosis infection (LTBI) prevalence survey was conducted using tuberculin skin test (TST) and Quantiferon test (QFT) in 1218 healthcare workers (HCWs) in Medellín, Colombia. In order to improve the prevalence estimates, a latent class model was built using a Bayesian approach with informative priors on the sensitivity and specificity of the TST. The proportion of concordant results (TST+,QFT+) was 41% and the discordant results contributed 27%. The marginal estimate of the prevalence P(LTBI+) was 62·1% [95% credible interval (CrI) 53·0–68·2]. The probability of LTBI+ given positive results for both tests was 99·6% (95% CrI 98·1–99·9). Sensitivity was 88·5 for TST and 74·3 for QFT, and specificity was 87·8 for TST and 97·6 for QFT. A high LTBI prevalence was found in HCWs with time-accumulated exposure in hospitals that lack control plans. In a context of intermediate tuberculosis (TB) incidence it is recommended to use only one test (either QFT or TST) in prevalence surveys or as pre-employment tests. Results will be useful to help implement TB infection control plans in hospitals where HCWs may be repeatedly exposed to unnoticed TB patients, and to inform the design of TB control policies.

We studied the monogenean communities of 34 species of butterflyfish from the tropical Indo-West Pacific, identifying 13 dactylogyrid species (including two species that are presently undescribed). Monogenean assemblages differed significantly between host species in terms of taxonomic structure, intensity and prevalence. Parasite richness ranged from 0 (Chaetodon lunulatus) to 11 (C. auriga, C. citrinellus and C. lunula). Host specificity varied between the dactylogyrids species, being found on 2–29 of the 34 chaetodontid species examined. Sympatric butterflyfish species were typically parasitized by different combinations of dactylogyrid species, suggesting the existence of complex host–parasite interactions. We identified six clusters of butterflyfish species based on the similarities of their dactylogyrid communities. Dactylogyrid richness and diversity were not related to host size, diet specialization, depth range or phylogeny of butterflyfish species. However, there was a weak positive correlation between monogenean richness and diversity and host geographical range. Most communities of dactylogyrids were dominated by Haliotrema aurigae and H. angelopterum, indicating the importance of the genus Haliotrema in shaping monogenean communities of butterflyfishes. This study casts light on the structure of the monogenean communities of butterflyfishes, suggesting that the diversity and complexity of community structures arises from a combination of host species-specific parameters.

The relationship between the semantic function of noun phrases and the way(s) in which they are realized morphosyntactically in a clause has been a topic of intensive research in the typological literature as well as for theories concerned with the syntax–semantics interface. Considering just noun phrases that function as direct objects, it has been shown for language after language that that there is a systematic relationship between the semantic function of an object (e.g. whether it is pronominal, definite, indefinite, etc.) and its morphosyntax (e.g. whether it requires special case marking, whether it triggers agreement, whether it exhibits special distribution in terms of word order, etc.). This paper aims to contribute to the already large body of evidence documenting the relationships between form and semantic function by providing a comprehensive survey of the morphosyntax of transitive constructions in Tagalog, focussing, specifically, on the relationship between the semantic function of the theme argument and the morphosyntactic strategies by which theme arguments are realized. Contrary to what previous studies have claimed, I show that specific noun phrases are attested as direct objects of active clause in Tagalog. An exception to this is pronoun and proper name themes, which must either be oblique marked to function as a direct object or be realized as a subject. Developing and expanding upon analyses in Rackowski (2002), I propose that the differential behavior of specific themes (pronoun/proper names on the one hand versus non-pronoun/proper name specific themes on the other) follows from a clausal architecture in which there are at least two VP-external positions to which specific themes must raise – a relatively high position for pronoun and proper name themes, and a position intermediate between vP and VP for all other specific themes. The distribution of syntactic positions available for the theme argument is claimed to follow from a proposal in Merchant (2006), pre-figured in Jelinek & Carnie (2003) and related work, that relational hierarchies of the type familiar from typological research – in particular, the definiteness hierarchy – are directly encoded in the phrase structure.

This paper investigates adverb extraction out of traditional adjective phrases (TAPs) like “extremely expensive”, in a number of Slavic, Romance, and Germanic languages, and establishes two novel generalizations regarding such extraction out of predicative and attributive TAPs, also showing what the (un)availability of such extraction reveals about the structure of TAPs cross-linguistically and in different constructions in a single language. I argue that attributive TAPs are never bare APs in languages that use only one adjectival form attributively. Languages that use two adjectival forms in the attributive position allow adverb extraction out of predicative and attributive TAPs, which indicates that adverb extraction is possible only if a bare AP is used in this position. More generally, I argue that extended projections of different lexical categories tend to be uniform within a language with respect to how much structure they project.

This paper assumes that the basic denotation of nouns can be that of kind or property and that the determiner system of a language is a direct consequence of this cross-linguistic variation. An analysis of how definiteness and specificity are marked across three languages with different determiner systems, namely, English, French and Mauritian Creole (MC), provides evidence of the co-relation between noun denotation and determiner system. Languages with kind denoting nouns (English and MC) admit bare nominal arguments, which are barred in French, whose nouns denote properties. However, English and MC differ in that English has an overt definite article, which is a lacking in MC. This null element requires licensing by an overt specificity marker in some syntactic environments. The English and MC definite articles are analyzed as operators that quantify over sets of kind denoting nouns, and they serve a different function from the French definite article, which is specified for number and selects properties.

The second-order visual mechanisms perform the operation of integrating the spatially distributed local visual information. Their organization is traditionally considered within the framework of the filter-rectify-filter model. These are the second-order filters that provide the ability to detect texture gradients. However, the question of the mechanisms' selectivity to the modulation dimension remains open. The aim of this investigation is to answer the above question by using visual evoked potentials (VEPs). Stimuli were textures consisting of staggered Gabor patches. The base texture was nonmodulated (NM). Three other textures represented the base texture which was sinusoidally modulated in different dimensions: contrast, orientation, or spatial frequency. EEG was recorded with 20 electrodes. VEPs of 500 ms duration were obtained for each of the four textures. After that, VEP to the NM texture was subtracted from VEP to each modulated texture. As a result, three different waves (d-waves) were obtained for each electrode site. Each d-wave was then averaged across all the 48 observers. The revealed d-waves have a latency of about 200 ms and, in our opinion, reflect the second-order filters reactivation through the feedback connection. The d-waves for different modulation dimensions were compared with each other in time, amplitude, topography, and localization of the sources of activity that causes the d-wave (with sLORETA). We proceeded from the assumption that the d-wave (its first component) represents functioning of the second-order visual mechanisms and activity changes at the following processing stages. It was found that the d-waves for different modulation dimensions significantly differ in all parameters. The obtained results indicate that the spatial modulations of different texture parameters caused specific changes in the brain activity, which could be evidence supporting the specificity of the second-order visual mechanisms to modulation dimension.